The present invention relates to a flocculant based gelation-solidification-disinfection system for the treatment of biomedical waste. Particularly, the present invention relates to the process for preparation of disinfecting composition comprising of a selected nanomaterial as its sol in water and a poly-amino acid containing a basifying agent, which when mixed with solid or fluid waste samples at a defined volumetric and/or weighted composition leads to instantaneous flocculation/gelation/solidification with >99.9% microbial disinfection. More particularly, the present invention relates to a disinfecting device for the treatment of biomedical waste.
Mismanagement of infectious wastes such as biomedical test samples leads to the transmission of microbes/toxins/viruses and further steer the spread of contagious and infectious diseases. According to a position statement (2000) by WHO, improper management of medical wastes such as infected hypodermic needles and syringes has caused infections pertaining to hepatitis B (21 million cases), hepatitis C (2 million cases) and HIV (0.26 million cases) worldwide. The following statements quoted from WHO undermine the significance and the need for proper medical waste management: “Poor management of medical waste potentially exposes healthcare workers, waste handlers, patients and the community at large to infection, toxic effects and injuries, and risks polluting the environment. It is essential that all medical waste materials are segregated at the point of generation, appropriately treated, and disposed of safely” (reproduced from http://www.who.int/topics/medical_waste/en/).
Adding a flocculating agent to liquid waste reduces the risk of spills and aerosolization. Solid wastes such as cotton, sharps as well as tissue papers may also lead to spread of infections, further, simple absorbers or hypochlorites that are currently in use are not always capable of treating such wastes. If the flocculating/gelling agent contains a disinfectant, it may be possible to dispose of the waste as non-regulated medical waste, which is less expensive than red-bagging. Segregation, transportation and incineration of such disinfected medical wastes are easier, safer and also decreases the medical waste disposal costs for a healthcare facility.
Several strategies have been adopted for the management of liquid biomedical waste and include, but not limited to, sanitary sewer disposal methods, chemical treatments using 1% sodium hypochlorite solution with a minimum contact period of 30 minutes or 10-14 gm bleaching powder per liter of water, 70% ethanol, 4% formaldehyde, 70% isopropyl alcohol, 25% iodine or 6% hydrogen peroxide, solidification of liquid waste using dry super adsorbent polymers containing sanitizers or disinfecting agents like chlorine or glutaraldehyde, closed disposal systems, etc. Reference may be made to an article, “Liquid biomedical waste management: An emerging concern for physicians, Biswal S, Muller J Med Sci Res 2013, 4, 99-106 which states that the culture media containing high microbial loads or rich protein contents requires rigorous disinfection procedures, wherein inactivation is achieved using 5.23% sodium hypochlorite in a 1:10 dilution for a minimum of 8 hours inside a secured vessel followed by disposal down the sanitary sewer and subsequent flushing with a lot of cold water for at least of 10 minutes.
Solidification systems (super adsorbents) are deemed advantageous over other methods for the treatment and safer disposal of biomedical fluid wastes. Superabsorbent polymers are generally prepared by polymerizing unsaturated carboxylic acids or derivatives thereof, including, but not limited to, acrylic acid or its or metal/ammonium salts and alkyl acrylates, using an internal cross-linking agent such as oligo-functional monomers including, but not limited to, bisacrylamides, triacrylates, dimethacrylates, or triallylamines.
Several patents have educated the development of such solidification systems. Application Reference may be made to the U.S. Pat. No. 7,291,674B2 wherein surface cross-linked superabsorbent polymers with good liquid retention, permeability, and mechanical strength based on the absorbent structure.
Reference may be made to the U.S. Pat. No. 8,450,389B1, wherein one or a plurality of surface cross-linked superabsorbent particles in combination with a plurality of second particles for liquid solidification with reduced gel block and a method of solidifying liquid medical waste.
Reference may be made to the another patent U.S. Pat. No. 9,533,081B1, wherein a portable wound therapy system comprising a plurality of surface cross-linked superabsorbent particles along with a container, a wound covering, and a packet and included a similar liquid solidification system with reduced gel block.
Reference may be made to the U.S. Pat. No. 5,391,351A, wherein a body waste fluid solidification device comprising a hydrophilic xerogel of partially hydrolyzed poly (vinyl acetate), cross-linked poly (vinyl alcohol), cross-linked hydroxyalkyl acrylates and methacrylates, polymers and copolymers of ethylene oxide and polymers and copolymers acrylamide.
Reference may be made to the U.S. Pat. No. 6,797,857B2, wherein a solidifier for the solidification of a volume of liquid with a known density, comprising of three adsorbents with varying densities, thereby achieving controlled stabilization of a flowable material throughout its overall volume.
Reference may be made to the U.S. Pat. No. 5,424,265A, wherein a capsule for absorbing liquid waste with a powder adsorbent material disposed within said capsule, the body of the said capsule being water soluble leads to the adsorption of liquid waste located within a suction canister.
Reference may be made to the U.S. Pat. No. 9,102,806B2, wherein a particulate superabsorbent polymer capable of absorbing water, aqueous liquids, and blood, and a process to manufacture the said superabsorbent polymers. The said super adsorbent comprises of a 1-10 wt % of a thermoplastic polymer of any class selected from polyolefin, polyethylene, linear low density polyethylene, ethylene acrylic acid copolymer, styrene copolymers, ethylene alkyl methacrylate copolymer, polypropylene, ethylene vinyl acetate copolymer, polyamide, polyester, blends thereof, or copolymers thereof, where the surface is treated with a neutralized multivalent metal salt solution having a pH value similar to that of human skin.
Reference may be made to the U.S. Pat. No. 8,403,904B2, wherein a superabsorbent polymer comprising an internal cross-linking agent consisting of a silane derivative having a minimum of one vinyl group or one allyl group attached to a silicon atom, and at least one Si—O bond with high centrifuge retention capacity.
Super adsorbing polymers, methods for their preparation and application in liquid solidification have been described by several patents, viz, EP2739660B2, US20130310251A1, EP0273141B1, U.S. Pat. No. 8,476,189B1, JP5527916B2, U.S. Pat. No. 5,578,318A, DE69815670T2 and U.S. Pat. No. 8,821,363B1.
Solid wastes including, but not limited to, used cotton, tissue papers, syringes and needles are generally disinfected using approved disinfectants and/or sanitizers and are incinerated or recycled. Waste burial or land-fills, disposal in cemented pits, immobilization using plastic foam, sand, cement or clay, low/medium/high temperature burning, controlled incineration, steam autoclaving, rotary kiln, microwave treatment, chemical treatment, shredding, melting, etc. are the general practices in disposing solid waste.
(Reference may be made to WHO @ www.who.int/, and Medical Waste Management, International Committee of the Red Cross @ www.icrc.org/). A 1-10% solution of bleach, or hypochlorites, sodium hydroxide or other chemical disinfectants are used to disinfect biomedical waste. Heat, alkaline digesters and microwaves are also used for this purpose.
Acrylate based solidifiers, though cheap and vastly available, are not devoid of disadvantages. They generally take 10-15 minutes for complete gelation and are not easily recycled. Further, they are non-biodegradable and also some acrylates are shown to be flammable. Studies have indicated that several acrylates and their raw materials can be carcinogenic. Manufacturing of acrylics has both health and environmental impacts. Several chemicals used in the manufacturing as well as the chemical waste from acrylic plants are toxic. Hypochlorite (bleach) is not always effective with high organic content waste such as blood. Further, a disinfection system capable of instantaneously treating, immobilizing and disinfecting both liquid and solid medical wastes is not found in literature.
The main objective of the present invention is to provide a disinfecting composition which is capable of treating and disinfecting solid and fluid biomedical waste samples via instantaneous flocculation, gelation or solidification.
Another objective of the present invention is to provide a safer and cost-effective strategy for managing the biomedical wastes including solid and liquid wastes, via the reduction of spillage and occupational exposure.
Yet another objective of the present invention is to provide a process for the preparation of disinfecting composition for disposal of solid and fluid waste collected in a device at the required point of care.
Still another objective of the present invention is to provide a composition for the preparation for disposal of solid and fluid waste collected in a device via flocculation, gelation or solidification and further to destroy or at least disinfect or deactivate the infectious agents in the wastes for the preparation for disposal including treatment and transportation of the samples.
This section describes the present invention in preferred embodiments.
In view of the above technical background, the present invention intends to disclose the development of a flocculant based gelation-solidification-disinfection composition for the treatment of biomedical waste.
Accordingly, the present invention provides a flocculant based disinfection composition comprising a solution A and a solution B wherein solution A is in a range of 0.1-2000 mg/mL, more preferably 1-200 mg/mL, 10-20% (v/v) of solution B; and the solution B is in a range of 0.1-700 mg/mL.
In an embodiment of the present invention, the solution A is poly-glutamic acid containing a base.
In another embodiment of the present invention, the base is sodium hydroxide.
In yet another embodiment of the present invention, the solution B is nanomaterial selected from the group consisting of oxides of titanium, aluminium (boehmite), silicon or phosphates of lanthanide elements.
In yet another embodiment of the present invention, the lanthanide is selected from cerium or lanthanum.
In still another embodiment of the present invention, the nanomaterial is in the range of 0.1-70 wt %.
In another aspect, the present invention provides a process for preparing the disinfection composition, comprising the steps of:
In an embodiment of the present invention, the poly-glutamic acid used in step (a) is in the range of 10-20% (v/v) of solution B.
In another embodiment of the present invention, the sodium hydroxide used in step (a) is in the range of 0.1-2000 mg/mL, preferably 100-500 mg/mL of poly-glutamic acid.
In yet another embodiment of the present invention, the pH of the solution A is in the range of 9-13.
In yet another embodiment of the present invention, the sample used in step (c) is selected from the group consisting of salt, metal salt, aqueous waste, saliva, urine, blood or any solid sample, cotton, tissue, paper, needle, or swabs alone or in combination thereof.
In another aspect, the present invention provides a disinfection disposal device filled with the disinfected composition, the device comprising of:
In an embodiment of the present invention, the upper system is filled with the solution A.
In another embodiment of the present invention, the middle system is filled with the sample.
In yet another embodiment of the present invention, the bottom system is filled with the solution B.
In still another embodiment of the present invention, the sample is solid or liquid waste.
Accordingly, in the present invention the attached illustrations/drawings are intended for the purpose of describing and understanding invention in detail and not to limit the invention or its scope or both there.
In view of the above technical background, the present invention provides a flocculant based gelation-solidification-disinfection composition for the treatment of biomedical waste. The treatment composition described herein comprises of a selected nanomaterial as its sol in water and a poly-amino acid containing a basifying agent, which when mixed with solid or fluid waste samples at a defined volumetric and/or weighted composition leads to instantaneous flocculation/gelation/solidification with up to 100% microbial disinfection.
The main objective of the present invention is to provide a disinfection composition for the preparation for disposal of solid and fluid wastes collected in a collection vessel combined with the destruction, disinfection or deactivation of infectious agents including microorganisms such as, but not limited to, bacteria, fungus etc., viruses and other toxins, whereby the disposal including treatment, handling and transportation are deemed easier, safer and cost-effective.
Another aspect of the present invention provides a method to create a non-pourable environment for fluid medical wastes including, but not limited to saliva, urine, blood, etc. wherein risks related to spillage and occupational exposure are minimized, added with >99.9% microbial disfection.
In one aspect, the present subject matter is directed to the treatment of solid medical wastes including, but not limited to, cotton, tissue paper, swabs, needles, etc., wherein the risks related to accumulation of untreated and infected samples are minimized with >99.9% microbial disinfection.
Another aspect of the present invention discloses the volumetric composition of a sol of a defined nanomaterial selected from, but not limited to, oxides of titanium, aluminium, silicon or phosphates of lanthanide elements selected from, but not limited to, lanthanum or cerium in water at a predefined wt % with a biopolymer, specifically poly-amino acids, more specifically polyglutamic acid as its aqueous solution, containing a pH regulating base or alkali for complete disinfection of a predefined volume of fluid medical waste.
The invention also provides a method for the treatment of solid medical wastes including, but not limited to, cotton, swabs, needles or tissue paper, using a composition of a sol of a defined nanomaterial selected from, but not limited to, oxides of titanium, aluminium, silicon or phosphates of lanthanide elements selected from, but not limited to, lanthanum or cerium in water at a predefined wt % with a biopolymer, specifically poly-amino acids, more specifically polyglutamic acid as its aqueous solution, containing a pH regulating base or alkali, thereby rendering the samples non-infectious with >99.9% microbial disinfection.
Upon extensive investigations, the inventors of the present invention found that adding a poly-amino acid as its aqueous solution to a stable nanomaterial sol in water leads to instantaneous flocculation and the said flocculation process could further be controlled to effect gelation or solidification under carefully controlled conditions, depending on, but not limited to, the type of nanomaterial, concentration, volumetric ratio, etc.
The present invention provides a disinfection composition for the preparation for disposal of solid and fluid wastes collected in device at point of care, combined with the destruction, disinfection or deactivation of infectious agents including microorganisms such as, but not limited to, bacteria, fungus etc., viruses and other toxins, whereby the disposal including treatment, handling and transportation are deemed easier, safer and cost-effective. The addition of a flocculating agent to liquid waste reduces the risk of spills and aerosolization, whereas disinfection allows to dispose of the wastes thereof as non-regulated medical waste, which is less expensive than red-bagging. Segregation, transportation and incineration of such disinfected medical wastes are easier, safer and decrease medical waste disposal costs for a healthcare facility.
The present invention provides a volumetric composition of a sol of a defined nanomaterial selected from, but not limited to, oxides of titanium, aluminium, silicon or phosphates of lanthanide elements selected from, but not limited to, lanthanum or cerium in water at a predefined wt %, preferably 0.1-50 wt % titania (TiO2) sol in water, more preferably 1-5 wt % titania (TiO2) sol in water, preferably 0.1-60 wt % boehmite (alumina) sol in water, more preferably 5-10 wt % boehmite (alumina) sol in water, preferably 0.1-50 wt % lanthanum or cerium phosphate (LaPO4 or CePO4) sol in water, more preferably 1-5 wt % lanthanum or cerium phosphate (LaPO4 or CePO4) sol in water, preferably 0.1-70 wt % silica (SiO2) in water, more preferably 25-50 wt % silica (SiO2) sol in water with a biopolymer, specifically poly-amino acids, more specifically polyglutamic acid as its aqueous solution, at a preferred concentration of 0.1-2000 mg/mL, more preferably at a concentration of 1-200 mg/mL, containing a pH regulating base or alkali, the said base is hydroxides of alkali metals or alkaline earth metals, basic salts of metals and organic cations, more preferably sodium hydroxide at a concentration of 0.1-2000 mg per mL of the poly-amino acid, more preferably 100-500 mg per mL of the poly-amino acid, the said mixture leading to a complete disinfection of a predefined volume of fluid medical waste.
The present invention provides a self-disinfecting flocculant-based gelation-solidification composition for the treatment and disposal of biomedical waste. The treatment composition disclosed herein comprises of a poly-amino acid as its aqueous solution, the said solution basified to an alkaline pH>9 using a base, preferably pH>11, more preferably pH>13, the said base is preferably sodium hydroxide, and a selected nanomaterial as its sol in water, which when subjected to mixing with solid or fluid waste samples at a defined volumetric and/or weighted composition leads to instantaneous flocculation/gelation/solidification with up to 100% microbial disinfection.
The present invention provides a process for the treatment of solid medical wastes including, but not limited to, cotton, swabs, needles or tissue paper, using a composition of a sol of a defined nanomaterial selected from, but not limited to, oxides of titanium, aluminium, silicon or phosphates of lanthanide elements selected from, but not limited to, lanthanum or cerium in water at a predefined wt %, preferably 0.1-50 wt % titania (TiO2) sol in water, more preferably 1-wt % titania (TiO2) sol in water, preferably 0.1-60 wt % boehmite (alumina) sol in water, more preferably 5-10 wt % boehmite (alumina) sol in water, preferably 0.1-50 wt % lanthanum or cerium phosphate (LaPO4 or CePO4) sol in water, more preferably 1-5 wt % lanthanum or cerium phosphate (LaPO4 or CePO4) sol in water, preferably 0.1-70 wt % silica (SiO2) in water, more preferably 25-50 wt % silica (SiO2) sol in water, with a biopolymer, specifically poly-amino acids, more specifically polyglutamic acid as its aqueous solution, at a preferred concentration of 0.1-2000 mg/mL, more preferably at a concentration of 1-200 mg/mL, containing a pH regulating base or alkali, the said base is hydroxides of alkali metals or alkaline earth metals, basic salts of metals and organic cations, more preferably sodium hydroxide at a concentration of 0.1-2000 mg per mL of the poly-amino acid, more preferably 100-500 mg per mL of the poly-amino acid, thereby rendering the samples non-infectious with >99.9% microbial disinfection.
The present invention provides the disinfection composition, the composition comprising of the sol of one or a plurality of nanomaterials and pH regulated poly-amino acid, specifically polyglutamic acid, as its aqueous solution, at a preferred concentration of 0.1-2000 mg/mL, more preferably at a concentration of 1-200 mg/mL, containing a pH regulating base or alkali, the said base is hydroxides of alkali metals or alkaline earth metals, basic salts of metals and organic cations, more preferably sodium hydroxide at a concentration of 0.1-2000 mg per mL of the poly-amino acid, more preferably 100-500 mg per mL of the poly-amino acid, with effective flocculation/gelation/solidification of solid of fluid samples containing proteins, microbial cultures, salt or metal ions in high concentrations.
The present invention provides a method to create a non-pourable environment for free-flowing fluid medical wastes including, but not limited to saliva, urine, blood, etc. wherein risks related to spillage and occupational exposure are minimized, added with >99.9% microbial disfection. Samples of body fluids were simulated with spikes of high protein content, salt or sugar as described in the respective examples.
The other vital constitutional element in the present invention relates to the treatment of solid medical wastes including, but not limited to, cotton, tissue paper, swabs, needles, etc., that may also lead to spread of infections and simple absorbers or hypochlorites that are currently in use are not always capable of treating such solid wastes, wherein the risks related to accumulation of untreated and infected samples are minimized with >99.9% microbial disinfection.
Another aspect of the present invention is directed to creating all-in-one sample collection-solidification-disinfection device of requisite dimensions capable of collecting the solid or liquid sample, flocculating/gelating/solidifying the samples as and when required and disinfecting the same for preparation for its disposal.
Following examples are given by way of illustration and therefore should not be construed to limit the scope of the invention.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL TiO2 sol (2 wt %) in water was pipetted out into ten 8 mL glass vials. 10-100 μL polyglutamic acid solution was added to each of the above vials and mixed. Flocculation was found to occur in all the vial immediately upon mixing, whereas instantaneous gelation occurs upon addition of 70 μL or larger amounts of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL TiO2 sol (2 wt %) in water was added to 1 mL aqueous waste in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Excess sodium chloride (300 mg) was added to 1 mL TiO2 sol (2 wt %) in water in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Fe(II)-bipyridine complex (100 mg, Fe(bpy)3Cl2) was added to 1 mL TiO2 sol (2 wt %) in water in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Excess sodium chloride (300 mg) was added to 1 mL TiO2 sol (2 wt %) in water in an 8 mL glass vial, followed by Fe(II)-bipyridine complex (100 mg, Fe(bpy)3Cl2). 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Bovine serum albumin (BSA, 6% in water mimicing human blood, 1 mL) was added to 1 mL TiO2 sol (2 wt %) in water in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 100 μL polyglutamic acid solution was added to 1 mL SiO2 Sol (50 wt % in water) in an 8 mL glass vial and mixed. Instantaneous gelation leading to solidification occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL SiO2 sol (50 wt %) in water was added to 1 mL aqueous waste in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation leading to solidification occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Fe(II)-bipyridine complex (100 mg, Fe(bpy)3Cl2) was added to 1 mL SiO2 sol (50 wt %) in water in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation leading to solidification occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Bovine serum albumin (BSA, 6% in water mimicing human blood, 1 mL) was added to 1 mL SiO2 sol in water in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous gelation followed by solidification occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 100 μL polyglutamic acid solution was added to 1 mL Boehmite Sol (10 wt % in water) in an 8 mL glass vial and mixed. Instantaneous flocculation leading to gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL Boehmite Sol (10 wt %) in water was added to 1 mL aqueous waste in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous flocculation leading to gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Bovine serum albumin (BSA, 6% in water mimicing human blood, 1 mL) was added to 1 mL SiO2 sol in water in an 8 mL glass vial. 100 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous flocculation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. Bovine serum albumin (BSA, 6% in water mimicing human blood, 1 mL) was added to 1 mL SiO2 sol in water in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous flocculation leading to gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 100 μL polyglutamic acid solution was added to 1 mL LaPO4 Sol (2 wt % in water) in an 8 mL glass vial and mixed. Instantaneous flocculation leading to gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL LaPO4 sol (2 wt %) in water was added to 1 mL aqueous waste in an 8 mL glass vial. 200 μL polyglutamic acid solution was added to the above vial and mixed. Instantaneous flocculation leading to gelation occurred upon addition of polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH).
Artificial saliva was prepared according to the following two procedures: (i) Mixing 1.5 mM Ca(NO3)2, 0.90 mM KH2PO4, 130 mM KCl and 60 mM Tris buffer at pH 7.4 (Reference may be made to: Kirkham, J.; et al., Self-assembling peptide scaffolds promote enamel remineralization, J. Dental Res. 2007, 86, 426-430). (ii) Mixing sodium chloride (0.06 g), potassium chloride (0.072 g), calcium chloride dihydrate (0.022 g), potassium dihydrogen phosphate (0.068 g), disodium hydrogen phosphate dodecahydrate (0.086 g), potassium thiocyanate (0.006 g), sodium hydrogen carbonate (0.15 g), and citric acid (0.003 g) in 100 mL distilled water at pH 6.5 (Reference may be made to: Duffó, G. S.; et al., Development of an artificial saliva solution for studying the corrosion behavior of dental alloys. Corrosion 2004, 60, 594-602).
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL artificial saliva was taken in an 8 mL glass vial and 200 μL polyglutamic acid solution was added and mixed. 2 mL SiO2 sol (50 wt %) in water was then added and instantaneous flocculation leading to gelation occurred upon mixing.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 0.75 mL artificial saliva was taken in an 8 mL glass vial and 2 mL Boehmite sol (10 wt %) in water was added. 200 μL polyglutamic acid solution was then added and instantaneous gelation leading solidification to occurred upon mixing.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 0.3-0.4 mL artificial saliva was taken in an 8 mL glass vial and 1 mL TiO2 sol (2 wt %) in water was added. 100 μL polyglutamic acid solution was then added and instantaneous flocculation leading to gelation occurred upon mixing.
To 75 mL of distilled water in a container, urea (1.82 g) was added and shaken well to dissolve. Sodium chloride (0.75 g), potassium chloride (0.45 g) and sodium phosphate (0.48 g) were further added to the above mixture and mixed well until dissolved. The pH was adjusted to be between 5 and 7. Creatinine (200 mg) and albumin powder (5 mg) were added and mixed gently. The artificial urine thus obtained was further spiked with a few mg of glucose before each experiment.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL glucose spiked artificial urine was taken in an 8 mL glass vial and 200 μL polyglutamic acid solution was added and mixed. 2 mL SiO2 sol (50 wt %) in water was then added and instantaneous gelation leading to solidification occurred upon mixing.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 1 mL glucose spiked artificial urine was taken in an 8 mL glass vial and 1.5 mL Boehmite sol (10 wt %) in water was added. 200 μL polyglutamic acid solution was then added and instantaneous flocculation leading to gelation occurred upon mixing.
A 6% solution of BSA was prepared in distilled water. A small amount of red water soluble dye was then added to impart color.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 0.5 mL artificial saliva was taken in an 8 mL glass vial and 1 mL TiO2 sol (2 wt %) in water was added. 200 μL polyglutamic acid solution was then added and instantaneous flocculation leading to gelation occurred upon mixing.
A stock solution of polyglutamic acid at a concentration of 100 mg/mL was prepared in water and sodium hydroxide (360 mg per mL of polyglutamic acid solution) was added. 0.5 mL artificial blood was taken in an 8 mL glass vial and 200 μL polyglutamic acid solution was added and mixed. 1 mL SiO2 sol (50 wt %) in water was then added and instantaneous gelation leading to solidification occurred upon mixing.
A piece of swab (4 cm) was taken in an 8 mL glass vial. 5 mL TiO2 sol (2 wt %) in water was added to the vial (so that the swab was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the swab was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of swab (4 cm) was taken in an 8 mL glass vial. 5 mL SiO2 sol (50 wt %) in water was added to the vial (so that the swab was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous gelation leading to solidification occurred upon mixing and the swab was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of swab (8 cm) was taken in a 15 mL glass vial. 12 mL TiO2 sol (2 wt %) in water was added to the vial (so that the swab was almost immersed in the sol), followed by 2 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to separation of solid and liquid components occurred upon mixing. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A needle (4 cm) was taken in an 8 mL glass vial. 5 mL SiO2 sol (50 wt %) in water was added to the vial (so that the needle was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous gelation leading to solidification occurred upon mixing and the needle was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A needle (4 cm) was taken in an 8 mL glass vial. 5 mL boehmite sol (10 wt %) in water was added to the vial (so that the needle was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the needle was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A needle (4 cm) was taken in an 8 mL glass vial. 5 mL LaPO4 sol (2 wt %) in water was added to the vial (so that the needle was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the needle was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of cotton waste was taken in an 8 mL glass vial. 2 mL SiO2 sol (50 wt %) in water was added to the vial (so that the cotton was almost immersed in the sol), followed by 200 μL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous gelation leading to solidification occurred upon mixing and the cotton waste was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of cotton waste was taken in an 8 mL glass vial. 2 mL TiO2 sol (2 wt %) in water was added to the vial (so that the cotton was almost immersed in the sol), followed by 200 μL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the cotton waste was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of cotton waste was taken in an 8 mL glass vial. 2 mL LaPO4 sol (2 wt %) in water was added to the vial (so that the needle was almost immersed in the sol), followed by 200 μL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the cotton waste was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of cotton waste was taken in an 8 mL glass vial. 2 mL boehmite sol (10 wt %) in water was added to the vial (so that the cotton was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the cotton waste was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of tissue paper was taken in an 8 mL glass vial. 2 mL SiO2 sol (50 wt %) in water was added to the vial (so that the tissue paper was almost immersed in the sol), followed by 200 □L polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous gelation leading to solidification occurred upon mixing and the tissue paper was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of tissue paper was taken in an 8 mL glass vial. 2 mL TiO2 sol (2 wt %) in water was added to the vial (so that the tissue paper was almost immersed in the sol), followed by 200 □L polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the tissue paper was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of tissue paper was taken in an 8 mL glass vial. 2 mL LaPO4 sol (2 wt %) in water was added to the vial (so that the tissue paper was almost immersed in the sol), followed by 200 μL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the tissue paper was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
A piece of tissue paper was taken in an 8 mL glass vial. 2 mL boehmite sol (10 wt %) in water was added to the vial (so that the tissue paper was almost immersed in the sol), followed by 1 mL polyglutamic acid (c=100 mg/mL containing 360 mg/mL NaOH). Instantaneous flocculation leading to gelation occurred upon mixing and the tissue paper was immobilized in the solid matrix. The amount of the sol and the glutamic acid depends on the size of the solid sample.
Cultures of Escherichia coli and Staphylococcus aureus were prepared in Luria Bertiani (LB) medium and taken for test at 18 hours old stage where the colony forming units (cfus) are approximately 1-3×106 per millilitre for E. coli or S. aureus. (previously standardized based on optical densities at 600 nm). 1 mL of the nanomaterial (2 wt % TiO2, 50 wt % SiO2, 2 wt % LaPO4 or 10 wt % boehmite) sol in water was spiked with 0.5 to 1.0 mL of the bacterial suspension (spiking solution) and mixed by swirling the bottle. Aqueous Polyglutamic acid solution (100 mg/mL, containing 360 mg sodium hydroxide per mL of the polyglutamic acid solution) was added such that its concentration is 10% of the total volume (including spiking solution), when the whole mixture becomes a gel. The gel is mixed well and diluted 10× in sterile saline and 100 μL of the diluted solution was plated onto LB agar plates and incubated over night at 37° C. Parallely, the original bacterial suspension was diluted serially in sterile saline and 100 μL of the appropriate dilutions were plated on LB agar plates and incubated as for the test sample that served as controls. Colonies were counted the next day and based on applied dilution, the number of CFUs/mL of the original bacterial suspension added to the sol and the CFUs in the gelled disinfectant were calculated. Efficiency was calculated as follows: [(No. of CFUs in Bacterial suspension—No. of CFUs in the gelled disinfectant)/No. of CFUs in Bacterial suspension]×100 and expressed in percentage.
An all-in-one sample collection-disinfection-disposal device for fluid samples was prototyped as follows: Three plastic collection vials were mounted one on top of the other such that the top vial contained polyglutamic acid solution (100 mg/mL with 360 mg sodium hydroxide per mL of the glutamic acid solution), the middle one for sample collection and the bottom one prefilled with the requisite amount of the nanomaterial (2 wt % TiO2, 50 wt % SiO2, 2 wt % LaPO4 or 10 wt % boehmite) sol. The design allows the top compartment to be unscrewed and the samples could be collected in the middle compartment. Once collected sample is tested, the remaining sample could be flocculated, gelled or solidified by initially allowing the sample to mix with the nanomaterial sol by breaking the junction between the middle and bottom compartments followed by the addition of polyglutamic acid from the top compartment by breaking the junction between the top and middle compartments. The mixing of the three fluid mixtures allow for complete pathogenic disinfection as evidenced in Example 37.
An all-in-one sample collection-disinfection-disposal device for solid samples was prototyped as follows: A plastic collection container for solid samples (Eg: cotton waste) was mounted on its top with another smaller plastic vial such that the top vial contained polyglutamic acid solution (100 mg/mL with 360 mg sodium hydroxide per mL of the glutamic acid solution), and the bottom one was half-filled with the requisite amount of the nanomaterial (2 wt % TiO2, 50 wt % SiO2, 2 wt % LaPO4 or 10 wt % boehmite) sol. The design allows the top compartment to be unscrewed and the solid samples could be collected in the bottom compartment. Once ample number of solid samples are collected in the bottom container, it could be flocculated, gelled or solidified by allowing the sample and the nanomaterial sol to mix with polyglutamic acid solution by breaking the junction between the two compartments. The mixing of the solutions and gelation allow for complete pathogenic disinfection as evidenced in Example 37.
Number | Date | Country | Kind |
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202011039050 | Sep 2020 | IN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/IN2021/050032 | 1/13/2021 | WO |